blistering is not likely in 5F, quite to teh contrary. You will feel running heaven. Do not get distracted by snow. You can go out for 10 minutes run, regardless of the freezing temp, preferably use cleared footpath or road, not the snow-trail combo as that will not teach You to run correctly. For the snow-trails, I use rubber soccer training shoes, the sole is like aquasocks or 5F, but it has big rubbers spikes, and has thicker toe box from rubber - giving some protection from unexpected branches or rocks. I got these from EU - I think they are still made in Czech in teh same factory where Zatopek was working. The sole of it is soft and could be bent any way so there is no motion control at all and absolutely no cushioning, but gives good traction in snow-mud condition. I also have size bigger so could fit 2 thick sock for those longer freezing runs. The same with Aquasock - have bigger size and fit warm socks for longer freezing winter sessions.

First run in my Classics today. I kept it on the treadmill (40 and raining outside) and to a 5k just in case. Wow. They felt great. I suspect running in minimal shoes helped ready for this however, the 5F were very comfortable. Since it was a short run, I don't expect any soreness. I did/do feel a couple of different muscles in my feet that were worked for the first time. My gait is already to mid/forefoot strike and my heels barely touched the belt at all and when they did it was more of a brushing feel. I was able to feel my footfall wrt to my center of gravity and could tell quickly when I was getting ahead of myself. I really like the shoes and look forward to putting some serious mileage runs on them in the near future. BTW - I did wear them around the house for a couple of hours prior to the run to get used to the feel on the toes.